The separation of database read and write means to ensure the stability of database products. Many databases have dual-machine hot backup functions. That is to say, the first database server is a production server that provides external addition, deletion, and modification services; the second database server mainly performs read operations.
Read-write separationIn order to ensure the stability of database products, many databases have dual-machine hot backup functions. That is to say, the first database server is a production server that provides external addition, deletion, and modification services; the second database server mainly performs read operations. ·
Principle:
Let the master database (master) handle transactional add, modify, and delete operations (INSERT, UPDATE, DELETE), and the slave database (slave) Handle SELECT query operations.
Implementation method:
Through RAID technology, RAID is the abbreviation of English Redundant Array of Independent Disks. When translated into Chinese, it means "Redundant Array of Independent Disks". Sometimes Also referred to as Disk Array.
Simply put, RAID is a method of combining multiple independent hard disks (physical hard disks) in different ways to form a hard disk group (logical hard disk), thereby providing higher storage performance and performance than a single hard disk. Provide data backup technology.
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